English verb conjugation
COULD FILM

Regular verb: film - filmed - filmed

Affirmation

Simple form	V-ing form
I could film you could film he could film we could film you could film they could film	I could be filming you could be filming he could be filming we could be filming you could be filming they could be filming
Perfect	V-ing perfect
I could have filmed you could have filmed he could have filmed we could have filmed you could have filmed they could have filmed	I could have been filming you could have been filming he could have been filming we could have been filming you could have been filming they could have been filming

Negation

Simple form	V-ing form
I could not film you could not film he could not film we could not film you could not film they could not film	I could not be filming you could not be filming he could not be filming we could not be filming you could not be filming they could not be filming
Perfect	V-ing perfect
I could not have filmed you could not have filmed he could not have filmed we could not have filmed you could not have filmed they could not have filmed	I could not have been filming you could not have been filming he could not have been filming we could not have been filming you could not have been filming they could not have been filming

Interrogative form

Simple form	V-ing form
could I film? could you film? could he film? could we film? could you film? could they film?	could I be filming? could you be filming? could he be filming? could we be filming? could you be filming? could they be filming?
Perfect	V-ing perfect
could I have filmed? could you have filmed? could he have filmed? could we have filmed? could you have filmed? could they have filmed?	could I have been filming? could you have been filming? could he have been filming? could we have been filming? could you have been filming? could they have been filming?

Interro-negative form

Simple form	V-ing form
could I not film? could you not film? could he not film? could we not film? could you not film? could they not film?	could I not be filming? could you not be filming? could he not be filming? could we not be filming? could you not be filming? could they not be filming?
Perfect	V-ing perfect
could I not have filmed? could you not have filmed? could he not have filmed? could we not have filmed? could you not have filmed? could they not have filmed?	could I not have been filming? could you not have been filming? could he not have been filming? could we not have been filming? could you not have been filming? could they not have been filming?